Desempenho zootécnico e fisiológico de frangos de corte, na fase final de crescimento, submetidos a diferentes níveis de estresse por calor

• Ano de defesa: 2014
• Autor(a) principal: Arcila, Juan Carlos Pareja
• Orientador(a): Tinôco, Ilda de Fátima Ferreira
• Banca de defesa: Albino, Luiz Fernando Teixeira
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Federal de Viçosa
• Programa de Pós-Graduação: Mestrado em Engenharia Agrícola
• Departamento: Construções rurais e ambiência; Energia na agricultura; Mecanização agrícola; Processamento de produ
• País: BR
• Palavras-chave em Português: Frango de corte; Avicultura; Ambiência; Bem-estar animal
• Palavras-chave em Inglês: Broiler; Poultry; Ambience; Animal welfare
• Área do conhecimento CNPq: CNPQ::CIENCIAS AGRARIAS::ENGENHARIA AGRICOLA
• Link de acesso: http://locus.ufv.br/handle/123456789/3671

The ambient temperature can influence the performance of birds, such as feed intake, animal welfare, productivity, cost of production and the maintenance requirement. Thus, in countries with tropical and subtropical climates, as is the case of Brazil, intense solar radiation and high values of temperature and relative humidity, especially in the summer, create conditions of thermal discomfort generating considerable economic losses due to reduction in performance and increased mortality of animals. The objective of this work was to study the influence of different levels of thermal stress from the environment, including granges of comfort(25°C), lighta stress(28°C), moderate heat(31°C), high heat (34°C) and severe heat (37°C), on the performance of broilers in the late growth(22-42 days), housed in environmental chambers. Have been determined the physiological and behavioral parameters of chickens, according the specific ranges of temperature and calculated the Temperature Index Black Globe Humidity(ITGU), for control and evaluation of the thermal environment of the treatments. The study was conducted in five climate cameras located in the experimental area of Center for Research in Agro-Industrial Ambience and Engineering Systems (AMBIAGRO) Rural Ambience Constructions and the Department of Agricultural Engineering, Federal University of Viçosa, Viçosa-MG, 150malechicksofone day old Cobb strain, withuniformweights45,36grams. The birds were on a bed of coffee hulls in thickness from 10 cm in order to play a field environment throughout the experimental period. This research was conducted in two stages, a pre-trial phase for the preparation of birds for research, ranging from the 1st day of life the chicks until the end of the 3rd week of life (1-21 days) and a test phase with 140 chicks, between the beginning of the 4th week of life until the end of the 6th week (22 to 42 days of live), in a completely randomized design, with belt thermal environments, four replicates per treatment and seven birds per unit experimental. Feed and waterwere supplied libitumand duringall the time, at nightall birds were keptinthermal comfort. In general, birds kept in temperature of light heat (28°C), according to literature as already causing heat stress during the three last week of life of chickens, performed better than those exposed to other situations, indicating this would be the ambient temperature to the desired setting for birds in its final phase environment, compared with originating the other treatments, including those who remained at recommended temperature as thermal comfort throughout the experimental period. Based on regression analysis of results ITGU, it was observed that at 28°C showed values 72,9 ± 1,4 for the fourth week, 75,5 ± 1,8 for the fifth week, and 73,7 ± 1,8 for the sixth week. The increase of 3,0°C in the process of creating of birds in relation to ambient temperature currently used in the literature in the second stage of creation of broilers it is feasible to improve the production rates of birds and has less waste of electrical energy in the process of cooling the environment, fitting for this, a readjustment of parameters currently used in poultry production in Brazil.